The present invention relates to recovery and treatment of underground mineral deposits by a multitude of directional and multi-functional wells drilled from the super daisy shaft through which the dynamics and dragging forces of fluid means is developed synergistically with complex rubblization and other techniques, and more particularly where the part of the array of wells assist in creation of the pressurized barriers to contain the exploitation field for treatment and recovery of minerals.
For example for one of the minerals: Sulfur, the recovery from underground deposits has been attempted with some limited success. In the period 1891-1915, Herman Frasch obtained patents for the Frasch mining method. This method was initially developed for diapiric salt domes located in the area of the Gulf of Mexico. The salt domes in their uppermost parts, called xe2x80x9ccap rockxe2x80x9d, also contain native sulfur deposits that are encapsulated and insulated from the surrounding permeable rocks by thick crusts of clay formations. The xe2x80x9cFrasch-ablexe2x80x9d deposits were so well sealed, that as an example, one of the mines xe2x80x9cOLD GULFxe2x80x9d in Texas, which was reopened after 33 years of dormancy, has retained almost its original production pressure and temperature, exceeding 80xc2x0 C.
The Frasch method used injection of super-heated water at 160xc2x0 C. into the encapsulated deposit, which melts and accumulates sulfur within the deposit. With use of an airlift, the sulfur is pumped out from the underground deposit to the surface by a randomly placed vertical combination well, which both injects hot water and receives the molten sulfur from the deposit. The injected hot water passes slowly through the confined, autoclave-like deposit, losing its temperature as it rises to the surface through so-called xe2x80x9cbleed-water wellsxe2x80x9d to dumping reservoirs. It was assumed that to economize heat losses, the bleed-water wells ought to be situated at the most remote peripheral parts of the deposit.
The Frasch method cannot be used for bedded type sulfur deposits, which were discovered in abundant amounts in Poland in 1953 (over one billion tons of mineable crystalline sulfur), followed by later discoveries in Russia (one hundred million tons of crystalline sulfur) and in Irag (two hundred million of crystalline sulfur). Bedded type deposits in Poland and Iraq were shallower than the salt domes in USA, and were often outcropped to the surface and spatially uninsulated. The Frasch method required at least a contained pressure of 8 bars and a melting temperature of 160xc2x0 C. for operation. Bedded deposits with outcrops obviously cannot be recovered with the Frasch method.
The present inventor disclosed in Sulfur Magazine, Exploitation of Bedded Sulfur Deposits by the Hydrodynamic Method, No. 120/1975, a method with international industrial application. Additional improvements were disclosed in U.S. Pat. No. 4,249,775 and in Recent Developments in Sulfur Mining By Underground Melting. Thermofluid Mining of Sulfur Deposits, B. Zakiewicz, Sulfur Magazine No. 184/1986. These improvements introduced re-circulation for the production water through the sulfur deposit for sulfur recovery and also re-circulation of brine throughout salt formations for recovery of mineral salts by pumping those liquids about submersible pumps and/or hot gasses. The conventional need for chemical treatment of recycled water was thereby avoided, and scale was eliminated in required heat exchangers. Recycled water being highly saturated with ions did not dissolved the carbonaceous sediment matrix and by the same prevents collapsing subsidence of the deposit structure. The distribution of the inclined production/injection wells was better organized to avoid a big energy losses in heat carrying pipelines In addition, catalytic combustor became well known and used as a soot-free heat source as well as for injectable combustion gases, which reduced energy consumption, improved the overall economy of recovery and eliminated any heat losses and pollution releases to the atmosphere. U.S. Pat. No. 4,869,555 discloses a method for hot water sulfur recovery with similar recycle of production water.
The maximum recoverability achieved in xe2x80x9cFrasch-ablexe2x80x9d deposits usually could not exceed 35% of original geological reserves (recovery ratio). The latter was exemplified by the total of forty exploited deposits, which were exceptionally rich and promising for the Frasch method applied. More than 50% of the production wells hitherto were terminated prematurely as a consequence of poorly working sulfur pumping systems in the low productivity wells. Cool, compressed air delivered into a low productivity well, results in sulfur solidification and subsequent liquidation of the well.
U.S. Pat. No. 4,289,354 by B. Zakiewicz, discloses the underground bore-hole mining of bituminous coal gasification projects for a pyrolytic process for fluidization of coal. The pyrolytic process is performed with injected oxygen, and control of the combustion pressure and temperature in the chamber is accomplished by its containment by concrete walls built along mining tunnels that outline the production field. Combustion is performed through drilling wells from the surface. The resulting lean pyrolytic gas had heating value of 3,351 kcal per cubic meter, capable of commercial use. Similar processes without containment in USA, Belgium and England have delivered pyrolytic gas having heating value of 2,469 kcal per cubic meter. It is evident from the above processes, that pyrolytic gasification requires densely spaced production wells.
U.S. Pat. Nos. 4,289,354 (Zakiewicz), 4,305,463, 4,550,779, 4,289,354, and 6,318,468 (Zakiewicz) disclose heavy crude recovery, where thermofluid and thermochemical processes are applied. The specific gravity of heavy crude could be 10xc2x0 API and below. In these processes xe2x80x9cdaisyxe2x80x9d wells were drilled with inclined six-leg extensions. The recycled high temperature fluids, enriched with organic solvents, were employed to fluidize and displace slow or non-flowable heavy crude. The complex combination of various techniques have produced large amounts of heavy and processed crudes, with or without use of vaporized organic solvents and catalytic combustors, generating soot-free combustion gases to carry heat to the formations.
None of the known so called xe2x80x9cBore-Holexe2x80x9d methods was able to develop a barriering dynamic confinement of the selected part of the sulfur, coal or crude-oil deposits as being developed at the peripheral circumference (enclosure boundary) of the mining field from one central point, which is the Super Daisy shaft. None of the existing methods was able to provide rubblization of the deposit synergistically with fluidization of the mineable miners and displacement of flowable minerals by dragging forces along both direction: centripetal from distant peripheral parts of the mining field towards centrally located collecting point and spiral- circular flows with turbulent swirling within confined mining field.
None of the existing methods exemplified in sulfur bore-hole mining was able to be utilized in mining the other minerals, practically with no significant adaptations, as it is possible in present invention.
The present invention is almost universally applicable for recovery, producing and processing of crystalline sulfur, heavy and light oil crude, natural free gas and its hydrates, pyrolitic and/or synthetic oil and gas from bituminous coal, brown coal and lignite, steam from underground combustion chambers in coal, salt leaching, uranium and other metals deposits leaching, biological mining, large systems of groundwater dewatering, large systems for toxic and radioactive underground disposal storage, strategic underground gas and petroleum storage, large groundwater intake systems, to name only the major applications.
The present invention comprises a synergistic confinement of the deposit by high pressure fluid barrier forming an enclosure boundary with respect to overburden and floor strata separated by one or more production strata containing desirable fluidizable deposits and/or potential reaction materials with simultaneous action of rubblization, mineral fluidization and dynamic-turbulent, centripetal displacement of fluidized minerals from the boundary strata of the mining field towards collecting point, which is Super Daisy Shaft. A centrally located Super Daisy Shaft delivers a highest pressure fluid to the enclosure boundary by way of envelope conduits extending laterally horizontal and/or downward from the Super Daisy Shaft (or a trench from which such conduits may also extend) into the production strata. Recovery conduits with ends within the envelope barrier inject lower pressure fluids and/or recover deposit fluids that are brought to the surface through the same Super Daisy Shaft. By withdrawal of higher pressure fluids and desired fluids from the product strata, the recovery conduits create a lower pressure well within the envelope high pressure barrier, thereby forming a circulation of production strata fluids from the envelope barrier centripetal toward the Super Daisy Shaft. In addition, within the envelope, the pressure in each individual directionally drilled well is diversified in a way which develops spiral-circular and centripetal flow of the fluidized mineral. This movement is resulted by dragging forces developed with use of large volume of the mobilizing and producing heat carrier, which can be water, steam or gasses. Jet pumps operating at the recovery conduit ends may be controlled in withdrawal of production strata materials so that a preferable pressure gradient is developed from the envelope barrier at high pressure to a recovery conduit at or near the Super Daisy Shaft.
Fluid flow along the described pressure gradient from the outer enclosure boundary to the Super Daisy Shaft creates and establishes production strata paths that with continuous fluid flow advantageously increase in size to extensively erode and/or free up desirable fluids from the production strata for recovery to the surface.
The present invention is useful in major classes of underground operations. Crude oil, sulfur and other minerals exist in production strata so that they can be recovered with the invention process. Similarly, pyrolytic gas and steam from underground coal can be more efficiently produced with the invention process, as well as recovery of desirable fluids from bacterial digestion of underground materials.